Etiket Arşivleri: Experiment-2

Alpha Amylase Production ( Experiment 2 )

Alpha amylase: EC

Amylases are important hydrolase enzymes which have been widely used since many decades. These enzymes randomly cleave internal glycosidic linkages in starch molecules to hydrolyze them and yield dextrins and oligosaccharides. Among amylases α-Amylase is in maximum demand due to its wide range of applications in the industrial front. With consumers growing increasingly aware of environmental issues, industries find enzymes as a good alternative over other chemical catalysts. α-Amylase can be produced by plant or microbial sources. Due to the advantages that microbial production offers, α-Amylase from microorganisms has been focused upon and preferred to other sources for production. The ubiquitous nature, ease of production and broad spectrum of applications make α-Amylase an industrially important enzyme. This report focuses on the microbial production of α-Amylase and its applications.

 Enzyme Production

In order to cultivate a microorganisms 4 major criteria you should be controlled or manipulate

1. Temperature

2. Initial pH

3. Oxygen

4. Carbon and Nitrogen sources

In order to control the temperature, incubator or water baths could be used. Initial pH is the other parameter which is critical for microbial growth. As all microorganisms have optimum temperature, they have also an optimum pH. Many microorganisms optimum pH is neutral pH (7). The other criteria is oxygen if the microorganisms is aerobic, you should supply air to the microorganisms. The carbon and nitrogen source is another important criteria. First of all these C and N sources are food of microorganisms so they should able to digest and uptake both C and N sources. Most of the Bacillus species can synthesis and secret extracellular alpha amylase. Due to this ability of Bacillus spesies we use Bacillus in order to obtain alpha amylase. For detection and quantification of alpha amylase activity we use DNS method as mentioned below.


FE 211 18.10.2004



Submitted By : Mutlu DEMİREL Group: 3


Ashless Paper , , HcL , Water , , Bunsen Burner , Methyl Orange, , Erlenmayer Flask , , Porcelain Crucibles , Graduated Cylinder , Furnace


In this experiment we calculated the weight and % of the sample ,


Gravimetric Analysis


The gravimetric determination of iron in soluble salt is done by converting all iron to , precipitating as a ferrichydroxide and igniting it to . The solubility of ferrichydroxide is very low and therefore quantitative precipitation can be achieved even in acidic solutions of ph up to 4. However , the precipitate is gelatinous and can not be filtrated through sintered glass crucibles because the pores of the crucibles are easily clogged with these types of precipitate. Therefore the precipitate has to be filtered through a filter paper. If the air oxygen is not sufficent , the compound may change to or even metallic iron by carbon from filter paper or reducing gases thar may firm when washing the filter paper.


5 g sample was added 1 ml Hcl and diluted to 250 ml. Then pulled filter paper and 2-3 drops of was added to this solution. After heating just to boil , 3 drops of methyl orange and was added to the solution. After that the solution solution was allowed to precipitate. When the supernatant was become clear , precipitate was allowed to coalugate an filter pulp for 15-30 minutes. Later the solution filtrated and washed with hot wash liquid .After testing the fresh portion filtrate with the filter paper was folded and put into a crucible.Then the crucible was charred off . After that the crucible was ignited at 800-900 in the furnace and weighed. So the weight of was found.


The volume of sample : 5ml

The density of sample : 60 g/L

The molecular weight of Fe : 55.847 g

The molecular weight of : 159.699 g

The mass of crucible : 12.0746 g

The mass of crucible + sample : 12.15.95 g

The mass of sample : 0.0849 g


In this experiment we calculated the weight and % of iron (III) with gravimetric analysis. We used to oxidize ions into before precipitating the solution. Then we added to make the solution alkali and precipitate reaction is obseved as ; While filtering the solution we washed the precipitate with wash liquid and tested the fresh portion filtrate with to observe ions. Washing to completed when no turbitidy is observed. Then the crucible was put on the bunsen burner with low fire. Low fire because of the carbon from the filter paper may reduce to Fe The result of the experiment may have some errors because of the ions that couldn’t be eleminated.Also carbon atoms from the filter paper may reduce to Fe althoug being careful.So the determined weight may not be only pure .